Applicants claim the foreign priority benefits under 35 U.S.C. 119 of Japanese Application No. 6-213509 filed Sep. 7, 1994. This Japanese Application and its translation are incorporated by reference into this Application. This invention pertains to modulator/demodulator or "modem" systems suitable connecting a computer or other data processing system to a telephone line or other communications network. More particularly, this invention pertains to a modem system that employs a novel mechanical interconnection of modem circuits to permit the manufacture of a physically small modem system suitable for a notebook or other small computer.
For a computer to be used to communicate across a public telephone network, an appropriate modem must be installed into the computer. Since the standards for data telephone exchange devices differ from country to country, a different data access arrangement circuit ("DAA") to connect the modem to a public telephone line must be installed each time the computer is used in a different country.
To eliminate such complexity, there is one proposal that involves the use of firmware that includes the standards for telephone data exchange devices for individual countries and that are written into a ROM. To standardize operation, the ROM is then included on an IC card that includes the modem (Japanese Unexamined Patent Publication No. 5-347647).
However, country specific information must be input to conform to the standards for telephone data exchange devices between countries. For example, when computers are used to communicate between one country and another that has different communication standards, country specific information has to be input for that country. Further, since the shape of modular jack connectors differs from country to country, modular jack connectors that match those for the respective countries are required.
Therefore, a modem board 50, as is shown in FIG. 3, has been proposed that employs a built-in DAA 24 to handle communications within Japan, the United States, etc., and a peripheral DAA 32 to handle communication in other countries that have different communication standards. The modem board 50 comprises an RJ11 connector 38 for the built-in DAA 24 and a MiniDin connector 28 for the peripheral DAA 32. A relay circuit 52 selects an analog signal received over analog lines 34 and 44, and couples the selected signal to a modem circuit 12 via a hybrid circuit 14.
However, it is difficult to physically fit the MiniDin connector 28, the RJ11 connector 38, and the relay circuit 52 on a small modem board suitable for a notebook computer. Therefore, it would be desirable to have a new and different mechanical arrangement of modem circuits, boards and connectors that would result in a compact modem system suitable for use in a notebook or other small computer, but still include a built-in DAA and the flexibility to connect to a peripheral DAA.